Bolt of material is chrome molybdenum (SCM) 435, also, because of the cold forging (threaded portion rolling) products, can be used with confidence in the strength more than enough. In addition the price is also relatively inexpensive, kind also abundant. Quantity also, so choose from a small amount to the box units, it has come in handy. In particular strength, because they are firmly engraved in the number in the bolt face, you can rest assured trust. It is very handy. Exactly in the low-cost, it is the strongest of the bolt.